128 AMERICAN JOUKNAL 



were curved towards each other like the horns of a cow.* Hepta- 

 tlactylus was distinguished by the development of seven spines,t 

 and 3IiUipeH of ten or eleven. | The genus Harpago would be 

 equivalent, so far as the diagnosis and known species are con- 

 cerned, to the natural group of which P. chiragra and P. rugosa 

 are the representatives. Hepta-dactylus includes the species P. 

 lamhis (Kleinian species 1, 2, 3, 4 and 5,) and P. scorpio or P. 

 pscudoscorptio (K. s. 6,) as well as one of the chiragra group 

 (K. s. 7,) to which, it is almost needless to say, the diagnosis 

 is not applicable ; finally, Millipes includes two nominal species 

 identifiable with P. millipeda. 



' The Kleinian names Harpago, ITeptadactglus, and Millipes, 

 were adopted for groups, as already indicated, by Morch and the 

 Adams brothers, but witli modified limits, so far as the species 

 enumerated were concerned ; at the sacrifice, however, in the 

 case of the Adams, of conformity between the characters of the 

 species and the diagnosis. 



The facts that Montfort, in 1810, applied the modified name 

 Pteroeeres to the Lamarckian genus, and that in 1822 Fabricius 

 gave the new name Digitata, are only of historic interest. 



§ 4. Revieav. 



The rules of the British and American associations for the 

 advancement of science are provisionally, at least, adopted. 



Under one of those rules, the pseudogeneric names connected 

 with species of this group by Aldrovandi, Klein and others will 

 be at once eliminated from consideration as ante-LinntBan and 

 not binomial. 



Under another rule, Humphrey's limitation of the genus 

 Stromhus to the present forms cannot be accepted, as neither the 

 genus itself nor those eliminated from it were in any manner 

 characterized. § 



* " Genus ii. Harpago. ? 252. Ab uncis dicitnr Trocho-Gonus, labiosus, 

 torosus, tympanosus, in sex murices acutos & aduncos fissus. Uliimus 

 ad mucronem longissimus ; duo sequentes & sibi oppositi sunt recurvi, 

 instar cornu bovini ; reliqui tres breviores, valde adunci. Testa ab extra 

 alba ; maculis fuscis picta. Pentadactylus, Pliniz." p. 98. 



t" Genus iii. Hepta-dactylus, ? 254. Est. Trocho- Conus, lahio in septem 

 murices diviso." p. 99. X " Genus iv. Millipes. ? 256. Est Trocho-Gonus 

 labiosus & cornutus ; ex labio 10. vel 11. murices curvos protendens ; 

 super dorso nodoso lineis rufis & nigris pictus." p. 99. 



I This rule is here adopted, as on another occasion, under protest. It 

 is doubtless the duty of an author to state the reasons for such changes 

 from an accepted method as he may deem advisable, and neglect to cha- 

 racterize such genera or other groups to which he iirst applies names, at 

 least gratuitously transfers the labor of interpreting his own thoughts on 

 another, and, it may be, is too much like obtaining credit on false pre- 



